Leviton GFSW1-T 15-Amp Self-Test SmartlockPro Slim GFCI Combination Switch Tamper-Resistant Receptacle with LED Indicator, 20-Amp Feed-Through, Light Almond For an added layer of protection, the GFCI regularly conducts an automatic internal test to confirm that it can respond to a ground fault Provides continuous ground fault protection - detects and trips on actual ground fault even when self-test is being conducted Status indicator light shows power and protection status as well as indication of line/load reversal Patented lockout action prevents reset if GFCI is damaged and cannot respond to a ground fault Slim, shallow design - reduced depth makes it easier to install